It’s been an important topic of discussion for the recovery: finding the blueprint for reestablishing Louisiana's wetlands? A group of environmental scientists at Southeastern Louisiana University said that blueprint can be found in Tangipahoa Parish, where cypress trees have grown quickly, thanks to sewage from the city of Hammond.

The Four Mile Marsh has acted as an outdoor laboratory for the scientists; a “massive kidney,” as Dr. Gary Shaffer, environmental scientist, puts it. And that kidney is growing.

The treated sewage from the city runs through a pipe three quarters of a mile long until it pours out of shower heads and into the marsh. There are 900 shower heads connected to the piping; 150 of them are turned on at a time. And the nutrient rich effluent pours into the marsh.

The pipeline cost $7 million dollars to build, but Hammond leaders said because the sewage doesn't go to final stage of treatment they're saving $2 million a year. In four years, the project will pay for itself.

“Here, we've got it manifolding out over 700 acres and the water gets completely cleaned at no cost, no maintenance, no operation costs, save electricity and grow the wetlands back like they used to be,” Shaffer said.

“It's much more than I ever thought that we'd have, at least this early,” said Chris Lundberg, SLU grad student.

“We came out to take water samples about a month ago, and that was the first time I had been out here really since the growing season had warmed up…and I was absolutely shocked,” said Bernard Wood, SLU grad student. “It was like walking into a jungle, where you can't see the person next to you, if he's standing five feet away from you. I can't see him, and we're talking about grass.”

The project is unique in many ways, but there are similar projects operating right now successfully in Mandeville, Thibodaux and Breaux Bridge. And Shaffer said any area of Louisiana with dying wetlands should be doing this. If they’re not, he said they're wasting their sewage.

“If you combine sewage effluent, treated sewage effluent with cypress/tupelo restoration, then you’re getting maximal growth rates, good biodiversity, and hurricane protection,” Shaffer said.

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The Four Mile Marsh has seen significant growth since the project began, Shaffer said.

And what's actually different about this project in the Four Mile Marsh is the level of engineering.

Shaffer's staff planted 5,500 cypress trees, and they’re growing at phenomenal rates. When the trees are tall enough, Shaffer believes their shade will kill off a lot of cattail and leave this marsh diverse and strong.

“The Pontchartrain Basin used to be 90% cypress, and we'd love to put 90% back,” he said.

What the scientists have learned in Hammond could be applied south of New Orleans, Shaffer said. He’s part of a group studying a plan for Orleans and St. Bernard parishes that would pump 100 million gallons a day into marshland in those parishes, 25-times the amount of treated sewage that pours into the Four Mile Marsh everyday.

“In a case like that, we can probably restore 10,000 to 15,000 acres of cypress/tupelo swamp for good,” Shaffer said.

Shaffer adds that a cypress/tupelo swamp offers far better hurricane protection than a levee.

“Imagine New Orleans with a belt of cypress wrapped around it, where a 20-foot storm surge hits the edge of that cypress and by the time it gets out the other end, that storm surge is a half a meter tall,” Shaffer said.

And Shaffer said there cannot be a drought when your constant water supply is driven by flushing toilets.

The scientists expect the Four Mile Marsh to look like a real forest in ten years. By that time, Shaffer said there should be many more projects like it, rebuilding Louisiana's wetlands.